1. Field of Invention
This invention relates to a method and an apparatus for winding webs of paper, board or the like on a core, wherein the wound web roll is supported on two adjacent drums, which also serve in driving the web roll.
When a roll of the desired size has been formed it is important that the completed roll can be removed, a new core can be brought into the gap between the supporting drums, and the leading end of the web can be brought around the new core without unnecessary loss of time.
2. Description of the Prior Art
The published German Offenlegungsschrift 2 032 724 discloses a method, wherein a new core is pushed into the space formed by the supporting drums and the web roll from one side of the winder, while the web roll is still supported by the supporting drums. This method implies that there is free space corresponding to the width of the web adjacent to the winder, and this restricts the use of the method.
The U.S. Pat. No. 3,841,578 discloses a method and an apparatus for winding of webs, wherein a new core is brought in front of the gap between the supporting drums on that side which is opposite to the completed roll side and pushed to the winding side of the supporting drums through said space while the supporting drums are moved away from each other. This requires that at least one of the supporting drums can be moved towards and away from the other supporting drum. Since the supporting drums have to transmit the torque needed for winding, the drive means are connected to them, which makes the construction very complicated.
The U.S. Pat. No. 2,989,262 discloses a winder, wherein a new core is brought into contact with one of the supporting drums and the rider roll while the completed web roll is supported by the other supporting drum. When the web has been severed, the new leading end of web is brought around the core by means of air nozzles, the core is transferred to the gap between the supporting drums, and the completed roll is ejected to the side of the winder. This arrangement is suitable for winders, where the web is fed to the web roll from below.
When the winding of a new web roll starts, the leading end of the web must first be attached to the core. This is usually done by glueing whereby glue is spread on the core or on that side of the web which is facing the core. The end of the web is brought around the core by hand or by means of belts, air nozzles or other guiding means. The web can be fed to the winder in different ways, but usually it is fed upwards between the supporting rolls.